What command rolls back the last migration?

• rails rollback
• rails db:rollback
• rails undo migration
• rails migrate down

Which file defines Rails gems?

• routes.rb
• database.yml
• Gemfile
• schema.rb

Which convention does Rails follow?

• Convention over Configuration
• Configuration over Convention
• Code over Convention
• Manual Configuration Required

What is 'bundle install' used for?

• Running server
• Installing project dependencies
• Starting Rails console
• Running migrations

Which Rails command creates a controller?

• rails generate controller
• rails create controller
• rails controller new
• rails make controller

Which command creates a migration file in Rails?

• rails create migration
• rails generate migration
• rails migration new
• rails db:create migration

What does 'resources :posts' generate in routes?

• Only show action
• All RESTful routes
• Only index and new
• Custom routes only

Which Rails feature helps avoid N+1 queries?

• Callbacks
• Eager Loading
• Scopes
• Validations

Which gem is widely used for authentication in Rails?

• Pundit
• Devise
• Omniauth
• Sorcery

Which Rails feature is used for background jobs?

• ActionCable
• ActiveJob
• ActionMailer
• ActiveRecord

Which Rails module handles real-time features?

• ActiveSupport
• ActionCable
• ActiveMailer
• ActiveJob

Which gem is used for API serialization?

• FastJSON
• ActiveModelSerializers
• Jbuilder
• Both B and C

Which security feature prevents CSRF attacks?

• Cross-origin filters
• Authenticity Token
• Parameter Filtering
• Content Security Policy

Which method helps avoid SQL injection in Rails?

• Using sanitize_sql
• Using parameterized queries
• Using find_by_sql
• Using raw SQL

Which Rails cache store is suitable for distributed apps?

• FileStore
• MemoryStore
• RedisStore
• NullStore